The primary objective of this Phase II project is to develop an innovative benchtop instrument for use on-site at food processing facilities with high performance, ease-of-use, and a low per sample cost for rapid, specific, and sensitive detection of multiple pathogens including Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella Typhimurium in ready-to-eat (RTE) foods, such as processed meat and poultry products and fresh fruits and vegetables. Our proposed technique provides the ability to quantify pathogenic bacteria down to less than 10 cells/mL in less than one hour with a minimum of false positives or negatives. The proposed instrument is fully integrated and includes a cartridge containing multiple capillary column-based bioseparator/bioreactors (for pathogen capture), and a liquid core waveguide (LCW) optical detector (for pathogen detection). It will not require pre-enrichment of target bacteria in growth medium and all steps of the assay will require minimal operator skill. Microbial contamination of food products by pathogenic bacteria is a major concern of our society. Contaminated food is estimated to cause 76 million illnesses, 325,000 serious illnesses resulting in hospitalization, and 5,000 deaths in the United States each year. The economic impact of foodborne illness has been estimated as high as $10 billion annually. The Center for Science in the Public Interest reported that fruits and vegetables are the leading culprits in confirmed cases of foodborne illness in the United States. Of particular concern is the presence of pathogens in imported produce. Because of the persistence of these pathogens on fresh produce, both FDA and USDA have supported research on developing standardized methods to determine the efficacy of proposed sanitizer strategies for inactivating these pathogens on fresh produce. A heat kill step is not feasible for such foods. An obvious companion need in the U.S. food safety program is a rapid, simple method, such as is proposed here, to determine the number of pathogens that persist after the sanitizing step has been administered.